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All IPCC definitions taken from Climate Change 2007: The Physical Science Basis. Working Group I Contribution to the Fourth Assessment Report of the Intergovernmental Panel on Climate Change, Annex I, Glossary, pp. 941-954. Cambridge University Press.

Does cold weather disprove global warming?

What the science says...

A local cold day has nothing to do with the long-term trend of increasing global temperatures.

Climate Myth...

It's freaking cold!
"Austria is today seeing its earliest snowfall in history with 30 to 40 centimetres already predicted in the mountains. Such dramatic falls in temperatures provide superficial evidence for those who doubt that the world is threatened by climate change." (Mail Online)

It's easy to confuse current weather events with long-term climate trends, and hard to understand the difference between weather and climate. It's a bit like being at the beach, trying to figure out if the tide is rising or falling just by watching individual waves roll in and out. The slow change of the tide is masked by the constant churning of the waves.

In a similar way, the normal ups and downs of weather make it hard to see slow changes in climate. To find climate trends you need to look at how weather is changing over a longer time span. Looking at high and low temperature data from recent decades shows that new record highs occur nearly twice as often as new record lows.

New records for cold weather will continue to be set, but global warming's gradual influence will make them increasingly rare.

Further reading

Comments

On this issue, "climate change" is more apt than "global warming".
And "climate is weather averaged over time" is more explicit than "weather is not climate."

The 'weather' skeptic's defense will be: "They do it too. If there's a warm spell, the believers will say its due to global warming."
After years of temperature increases, it is harder for believers to restrain such statements. But they should be restrained. Weather IS variable.
In addition, maybe policymakers should just whisper among themselves, about a current event occurring more frequently in a global warming future...to avoid the shortening misquote, that GW caused the event???

WEATHER'S ONE MONTH EFFECT...
...even averaged over a month, local weather anomalies (dynamical fluctuations, more-or-less independent of forced long-term climate change) are much larger than the global mean temperature change of recent decades. Weather fluctuations or 'noise' have a noticeable effect even on monthly-mean global-mean temperature, especially in Northern Hemisphere winter. Weather has little effect on global-mean temperature averaged over several months or more. The primary cause of variations on time scales from a few months to a few years is ocean dynamics, especially the Southern Oscillation (El Nino-La Nina cycle)...
Columbia.edu

COLD EXTREMES HAVE WARMED MORE...
In the last 50 years for the land areas sampled, there has been a significant decrease in the annual occurrence of cold nights and a significant increase in the annual occurrence of warm nights...Decreases in the annual occurrence of cold days and increases in hot days, while widespread, are generally less marked. The distribution of minimum and maximum temperatures have not only shifted to higher values, consistent with overall warming, but the cold extremes have warmed more than the warm extremes over the last 50 years.
IPCC AR4 WGI FAQ 3.3

REGIONAL EXCEPTIONALISM FOR GW FUTURE COLD SPELLS..?
It is also likely that a warmer future climate would have fewer frost days (i.e., nights where the temperature dips below freezing)...There is likely to be a decline in the frequency of cold air outbreaks (i.e., periods of extreme cold lasting from several days to over a week) in (Northern Hemisphere) winter in most areas. Exceptions could occur in areas with the smallest reductions of extreme cold in western North America, the North Atlantic and southern Europe and Asia due to atmospheric circulation changes.
IPCC AR4 WGI FAQ 10.1

RECORD HIGH TEMPERATURES FAR OUTPACE RECORD LOWS ACROSS U.S.
...The ratio of record highs to lows is likely to increase dramatically in coming decades if emissions of greenhouse gases continues to climb...
If temperatures were not warming, the number of record daily highs and lows being set each year would be approximately even. Instead, for the period from January 1, 2000, to September 30, 2009, the continental United States set 291,237 record highs and 142,420 record lows...
The study also found that the two-to-one ratio across the country as a whole could be attributed more to a comparatively small number of record lows than to a large number of record highs. This indicates that much of the nation's warming is occurring at night, when temperatures are dipping less often to record lows. This finding is consistent with years of climate model research showing that higher overnight lows should be expected with climate change...
"One of the messages of the study is that you still get cold days...Winter still comes..."
...analyzed several million daily high and low temperature readings taken over the span of six decades at about 1,800 weather stations across the country....a quality control process at the data center..looks for such potential problems as missing data as well as inconsistent readings caused by changes in thermometers, station locations, or other factors...
Meehl et al, ucar.edu Press Release, November 12, 2009

What do you think about Anthony Watts' attempted debunking of the Meehl 2009 report by complaining that it "cherry picked" temp records from 1950 on when 1930 had more record lows than highs? See http://wattsupwiththat.com/2009/11/16/why-ncars-meehl-paper-on-highlow-temperature-records-is-bunk/

It looks to me like Watts is really looking at numbers of record highs and lows and not ratios of highs to lows, but nonetheless it would be nice to see a debunking of the debunking. Overall, it would be even nicer to see a global report on record highs vs record lows to see if the trend Meehl et. al. found in the U.S. is really a global phenomena.

@djb95054 Watts' attempt isn't much of a debunking. Everything he mentions is addressed in the original paper. I mean what do you think is the more robust analysis, a weatherman's report of the records across a few dozen states or the actual record from 2000 stations over decades. See the y-axis above that's 5e+05! 500,000 measurements! Watts' plots show maybe 50 self-reported measurements. The statistical error on that alone is > 10%. Ask Watts to put this in excel and tell us the error on the slope. And he says things like there were 10 lows and 8 highs in 1930s or something like that. Do yourself a favor, read the original paper--you'll find the analysis 5e+05 times more robust.

@rader5 Okay, so the Meehl paper is more robust. I get that. But my question was more about the charge of "cherry picking" data from 1950 on, as opposed to including the 1930's and earlier. Is there a reason the Meehl paper starts in the 1950's?

Response: The 1950 to 2006 period was chosen because of the decision to use continuous station records. They chose this period to avoid any effect that would be introduced by a mix of shorter and longer records. The final result (the increasing ratio of record high versus record lows) isn't dependent on the start date of 1950.

On the lighter side: Since we had such a cold winter in North America, there was an uptick in the 'all that snow means global warming doesn't exist' hysteria. Bet we won't here much about this:

"It’s on the calendar. It’s widely advertised. This year, everybody knows about it but the trees. And they are the central characters in Vermont’s annual maple syrup open house this weekend, when tourists descend on the state to watch trees being tapped and sap being boiled.
Sugaring season ended early for many syrup farmers in southern Vermont, sabotaged by unseasonably warm weather." NY Times, 27 March 2010 (http://www.nytimes.com/2010/03/27/us/27syrup.html)

Muoncounter, it's a case of wheels within wheels. Not only are crypto-Communists trying to end our Western lifestyle by confiscating our incandescent lightbulbs, but at the same time the ruthless Canadians are extracting petroleum from tar sands, selling it to us Americans and then tricking us into burning it specifically so more C02 will be released, driving up temperatures, thus pushing the syrup industry north of the Canada-US border. They'll be selling that syrup back to us hungry, desperate pancake eaters later. It's a dastardly plot, one of many.

This is an excellent topic page - and one of the more insidious errors. Our personal experience, and by extension the personal experiences of people we know, tend to have a lot of weight on our judgement. So do more immediate events - what happened last week is more immediate, more forceful in our minds, than what happened a month ago.

We also place extreme weight on extraordinary events: a freak snowstorm gets talked about for years, even if the winter in which it occurred was on average pretty mild!

So for anyone collecting anecdotes or news stories about extreme weather events - I would strongly recommend looking at the statistics to judge the trends. Individual extreme events tell you very little...

It's unfortunate that the graphs in this post are for the US only. In an attempt to find similar data for the world as a whole, I ran across the website of Maximiliano Herrera, who has compiled data on weather stations that set new high or low records every year since 2002.

So far, in 2010 there have been 337 warm records versus 13 cool records.

In 2009, the ratio was 80 (warm) to 15 (cool).

In 2008, it was 40 (warm) to 18 (cool).

In 2007, it was 133 (warm) to 9 (cool). And so on...

It would be nice to find a more official or peer-reviewed analysis of this.
------------------------

(Moved from the other thread about impending ice ages, per the moderator's request)

Extreme events, by definition, are on the tail of the probability distribution. Events in the tail of the distribution are the ones that change most in frequency of occurrence as the distribution shifts due to global warming.

For example, the "hundred year flood" was once something that you had better be aware of, but it was not very likely soon and you could get reasonably priced insurance. But the probability distribution function does not need to shift very far for the 100-year event to be occurring several times a century, along with a good chance of at least one 500-year event.

Tom Loeber, instead of pasting loads of links to newspaper/online media articles giving records for anything from one to fifty years, how about links to officially recognised records that are significant, i.e. coldest on record, second coldest, etc.

Anything else can be safely ignored.

Also, please give a link to an official source that states that England was the "coldest in...140 years".

I notice that LA international airport reported a record cold temperature recently, so did a number of place in San Diego county. Brazil also recorded an historical record cold. I came across 6 reports all within the last 5 months of record cold in a few countries and that does not go into the first half of this year.

I don't readily see that mention of 140 year record cold in England. My mention of it is not that it happened but that I had seen it reported.

I think this web site is interesting. Seems the data there is well corroborated.

Yes, I was banned. Now, lets see if I still am as I hit the Submit button.

Oops. Here is that site I mentioned "Impacts & Causes of the Unusual Cold, Snowy & Stormy 2009~2010 Winter" http://sites.google.com/site/whythe2009winterissocold/

Well, look at that I am not banned but ask me, if I am not allowed to correct my mistakes and point out data that question assumptions here, does that demonstrate tolerance or open mindedness on the part of this web sites managers?

Response: You tread dangerous ground here. From the Comments Policy:

No accusations of deception. Any accusations of deception, fraud, dishonesty or corruption will be deleted. This applies to both sides. Stick to the science. You may criticize a person's methods but not their motives."

I judge this comment in violation of this, but to allow for you to see this and then have a chance to adjust future comments, will allow it to remain for a while.

I am not denying global warming. I know there are record extreme heat events. That recent spell in Russia was horrible, tens of thousands died. I don't know what is going to happen. Is the tipping point going to be run away global warming? Some 90% of the time for the last million years the earth has been colder than now. The interglacials have been the exception, like minor perturbations. The most stable state appears to be colder than now. I think that finding that melting of the caps immediately preceded glaciation for the last two major swings is interesting. I think I posted it elsewhere, the thread where I think I am still disallowed to post. What is wrong with the Hamaker hypothesis? The noctilucents seem to be a strong indicator that it has merit. Hamaker was apparently unaware of them and yet, their growing in frequency and duration is alarming and greatly supporting John Hamaker's thesis. I think it was Doug who posted a link to a paper purporting to explain how they don't signify any concern of climate change, the one that only used 45 years of their record out of 125 to predict they are basically of no concern. In that paper it also said they have never reached as much extent as when they first appeared. That is totally false. What leads people to give false data, to support the climate change deniers? My understanding is that fossil fuel companies pay millions each year to promote propaganda to keep us from seeking a carbon neutral future. Seen the satellite pictures of the carbon dioxide release we are doing? Who would deny that is not changing the weather, the climate?

All in all, I don't know what is going to happen. I do think there is a real possibility that without much warning or set trend, the climate could tip, tip drastically and very possibly to more cold. It appears to be like a higher energy phase state of the planet, triggered by global warming that does not correct itself for perhaps 100,000 years. I don't know. I think any one who says they know what the future holds is not adhering to science. Short term trends do not show tipping, do not show any proclivity for sudden change and yet, such has happened for the planet and they are liable to happen again. I, for one, am concerned enough to have two carbon neutral vehicles, to seek wind and photovoltaics for my electricity production, to farm my own food and live in a place that is recorded as having relatively stable weather right through ice ages. I will leave you to do what you want. I think it borders on being criminal to state you know what is going to happen rather than try to weigh evidence in an attempt to find most likely theories. I wish I were strong enough to get folks off the fossil fuel habit and start respecting this biosphere as our heritage and responsibility but I think we are oh so distracted by the need for money, by the need to make wars to secure the oil and the opium poppies to get more money. We lead a token existence.

Response: Don't stuff a single comment with multiple topics, when some of those topics are off topic for the particular post at the top of that particular page. We will simply delete the entire comment--even the part that is on topic. You need to pay attention.

Ah, I still can't post in that other thread. I wonder what is wrong with the data on this site that suggests all time record cold was recorded in the following countries during 2010:

Cuba, Philippines, Russia, Namibia, Antarctica, Australia, Bolivia

from http://www.mherrera.org/temp.htm

Maybe I am just interpreting that wrong? I mean, at first, I was thinking I was responding to the claim that record lows didn't happen in countries and then I see the claim appears to have shifted to record lows for within an entire country and not just locations.

I just got to leave this alone. I find forums and message boards are not functional in general.

Response: You are not banned from posting in any threads. You, and everyone else, have your comments deleted when they are off the topic of that particular thread. Most of the threads on this Skeptical Science site are narrowly focused on particular topics. You need to pay attention.

Tom Loeber wrote : "I wonder what is wrong with the data on this site that suggests all time record cold was recorded in the following countries during 2010:

Cuba, Philippines, Russia, Namibia, Antarctica, Australia, Bolivia

from http://www.mherrera.org/temp.htm"

You've virtually answered your own question there ! Those few countries had record lows in one, two or three locations (depending on which country you look at), to give a total of 13 minimum records - none of them all-time records.
The rest of the list shown ('Records registered during 2010') are for maximum temperatures (I haven't counted them all but there has to be about 350 of them), and include (unlike the minimums) all-time records.

17: "I wonder what is wrong with the data on this site that suggests all time record cold was recorded in the following countries during 2010:"

Perhaps nothing is wrong with the data, but something is wrong with the approach you've taken. Refer to the key line at the top of this posting: A local cold day has nothing to do with the long-term trend of increasing global temperatures.

Yes, for sure, I see that a vast majority of records are high. I just wonder. The climate is dynamic, not linear. We are changing more than one factor, the concentrations of more than just one greenhouse gas. Should we expect a dynamic system to respond only linearly? If the posts in the URL I just gave are records for locations then why did they miss the all time record low set at Los Angeles International airport this year or the ones in San Diego county or in other countries?

In that other thread my messages never post to be deleted. You can see that has led others to cross post here too. If that is not being banned from that thread then I have to seriously consider that this whole endeavor is dysfunctional, it is not working as the moderator suggests.

Response: Remember that moderation is dynamical, too. Overly-tight moderation constricts the mutual discussion of the science (and provokes questions as to motivations; a no-win scenario). Under-moderation results in chaos. We're human, and as such do the best we can, making allowances for the same by commenters.
Keep your comments focused on the post topic and everything should be fine.
Also realize that sometimes comments are deleted within seconds of being posted--perhaps before you have a chance to see them. And be sure that after you click the Preview button and verify that your comment appears as you intend, that you then click the Submit button to actually post it.

Who said anything about climate responding linearly? There are multiple inputs (solar variation, GHGs, aerosols, etc) and a complicated output. Hot years, cold years, differential heating from one part of the globe to another:

Any understanding of that system requires two things:
1 - we must look at the long term trends, not the daily (or even annual) variation and
2 - we must base our understanding on the work of the scientists who are the experts in these things, not on the vaporings of those who cherry-pick data or see everything through their pre-conceived notions.

I quite agree muoncounter. In considering climate, not just years or tens of years or even thousands of years, we should also consider hundreds of thousands of years as necessary because it shows a repeated oscillation that if not considered could lead to missing cues for worthwhile strategy determination. I find at times experts have been quite mistaken in a major way, a majority of them. I think more important than depending on hear-say and the like, attempt to get a grasp of the data yourself and draw your own conclusions. Always realize we can only hold onto an opinion. Socrates is quoted as having said "True knowledge exists in knowing you know nothing."

Thank you for the reasonable comment moderator. I will attempt to post to that other thread again the egregious false claim made in the paper posted on down-playing noctilucents again.

Tom Loeber wrote : "I find at times experts have been quite mistaken in a major way, a majority of them."

Do you indeed ? Care to name a few of those times ?

Tom Loeber wrote : "I think more important than depending on hear-say and the like, attempt to get a grasp of the data yourself and draw your own conclusions.

Quite right, partly, I think. Don't rely on hear-say, definitely (and that includes media reports, etc.) - rather, rely on the experts, the expert studies and the science. Draw your own conclusions if you wish (and there are many so-called skeptics on here who certainly do !), but don't think that your conclusions are as valid as anyone elses, especially if your conclusions go against the conclusions of the science.

Tom Loeber at 07:22 AM, what I think it actually comes down to is a persons ability or otherwise to think laterally.
Many of the examples in your links are of people demonstrating inability to think laterally.
Whilst most people like to think that they are lateral thinkers, unfortunately the education process most people pass through tends to reinforce the logical thinking processes, some institutions I have observed even actually discourage lateral thinking.
At lot depends on the staff at the institution, there are only so many "inspirational" educators around, many are the tried and proven "sloggers" that follow the logical processes that teaching by the book demands.
The climate change debate is an excellent example where the reliance on peer reviewed papers and the necessity for all processes to be reduced to an equation to explain the physics involved leaves little room for lateral thinkers, especially amongst those who are students of the subject.

#22: "not just years or tens of years or even thousands of years, we should also consider hundreds of thousands of years"
Nice. You went from worrying about daily lows at LAX to glacial cycles, which have nothing to do with the current situation. Isn't that called obfuscation, a tried and true denier tactic?

"at times experts have been quite mistaken in a major way"

Sure. But do you drive over bridges? They fall. Fly in airplanes? They crash. The work of experts is all around us; we can't live buried in the suspicion that they are all in cahoots and out to get us.

I spend far too much time reading papers and looking at publicly available data; I am glad to read an expert analysis to help me digest it all. The point is, I am willing to incorporate into my evaluation the analysis of someone who knows more than I do.

"Always realize we can only hold onto an opinion." Well, as the saying goes, you're entitled to your opinion. But you aren't entitled to your own facts.

Response: It's time to take this discussion to a more relevant thread. Anybody who wants to continue, please use the Search field to find posts about "consensus" and pick the one of those you think is most relevant.

Yeah. I think banning me from that other thread led to a cross post here by another other than me wanting to continue our discussion. Me thinks the moderators screwed up and essentially messed up two of their own offerings. Try to take it easy there mods. The heavy handedness is not what makes the best theories.

Response: There is no mechanism for banning any user from a particular thread. What you're seeing is more than likely a bug relating to the site (either HTML or PHP related).

Tom Loeber - The post you are referring to here was from me. I was following the request of the moderators to move the discussion to a more appropriate thread.

You were asked repeatedly to move the discussion yourself; the deletion of off-topic posts (off topic in the ice age thread) has been a standard of this site since it began. It's worth reviewing the Comments Policy.

That wasn't a cross post at all - it was a redirection to the appropriate thread. If we don't try to keep on focus in our discussions, it makes it impossible for anyone else to (a) see relevant postings and to (b) contribute to an ongoing exchange. If we toss useful information onto a thread where nobody will ever think to look for it, we're wasting our time!

This is not the appropriate thread. I was not posting that cold weather disproves global warming at all. It was not your post that alerted me as to where the conversation was happening, it was JMurphy's who started it out with my name. This place is too dysfunctional to facilitate understanding especially as the moderators appear to have a heavy hand with any one who does not adhere to their theories.

As individual weather events are not climate (as was covered by several people responding to you), this thread on "Does cold weather disprove global warming" is entirely appropriate for that discussion.

Your response to the question of evidence for "wide spread record cold" did not demonstrate what you wished - I'm just left wondering why that wasn't apparent from the multiple posts responding or the numerous moderator remarks directed to you.

If you didn't note my response on extrema or the redirect, I can only presume you weren't reading the posts in the thread or the moderator notes to you.

2/3 of Peru under state of emergency for cold not widespread enough for you? Multiple SA countries experiencing record cold not widespread enough for you? There was more too but it only takes one to counter your claim. KR, I am not saying that individual weather events are climate. All I was saying is there is evidence that the weather could snap to cold conditions with little or no warning. As far as I can tell the Hamaker hypothesis holds more credibility than the Milankovitch theory which is what I was and am still addressing. This is not the proper thread for that but as long as the moderators disagree and they cater to the idea that might makes right, perhaps the major fallacy of epistemic relativism along with "what you don't know can't hurt you" and "ignoranc is bliss" and "killing the messenger invalidates the message" they will continue to practice dysfunction. As far as that last goes, the mods somehow got the posts I made to the other thread to show up days after they had been posted, more pointed critique of the paper Mr. Bostrom linked to discounting noctilucents as a possible sign of climate change. I was presenting a possibility that the noctilucents are the missing piece of Hamaker's hypothesis that suggests global warming leads to a rapid climate change eventually with little warning trend, to ice age conditions. The mods went back after getting those posts to show and deleted them unless that too was a bug. I posted other recent research that found solar insolation is not to blame but actually earth's albedo and carbon dioxide concentrations are complicit with ice age starts, right in keeping with the Hamaker hypothesis.

This selective recall of yours does not help.

I mean, give me a break, you are inferring I'm quite the total idiot and it might just be fine and dandy with the mods for ad hominem to predominate against a person who does not kiss ass. I am very much into being open and honest and many do not have a world model that incorporates the utility of that.

As far as I can tell this message board is dysfunctional, the mods are exhibiting dysfunctional behavior and many of the participants keep on arguing apples to oranges to suggest the place caters to the dysfunctional. Well, as a Homo sap on planet earth the lack of wherewithal of my fellow human beings is my failing too so I too am dysfunctional as I do not exist in a vacuum. I have even been know to make mistakes and I have tried to correct them here and in the other thread. The "lets all gang up on the one who seeks to be logical" scenario I seem to be witnessing here is, again, a consequence of this idea that majority opinion determines truth. If anyone is truly interested in pursuing a better understanding of what is going on and what we should be trying to prepare for and avoid, those who disagree with the adopted stance, as long as they are not totally wacko, should be given lots of room, see past my frailties as a human being and see that quite possibly, the long term predictions for extreme cold and harsh winters ahead are not just a bunch of baloney. Maybe some of those are based on sound information that we shouldn't just ignore due to their not fitting in with the theory that lets the fossil fuel profiting companies off the hook. Did you see that Project Censored item that the US pentagon is the top polluter on the planet?

The description of what the "Policy" is here seems to be a list of what the mods think is okay for them to do and for anyone else who plays into supporting their perspective. Like many laws they are used against those who attempt to speak truth to power while letting the powerful get away with breaking them continuously and often. So it goes.

Response: The Comments policy defines what is and is not acceptable on this site. Avoid irrelevant personal attacks, stay on topic, and don't stray into politics and you'll be fine.

Widespread cold records during the (tied) hottest year, globally on record is consistent with the ideas presented in the Nature paper Early-warning signals for critical transitions. Technically we would describe this as a signal showing increased variance of a complex system.

Hey, Tom, I thought Hamaker said that the tropics would receive most of the warming, causing an intensification of the tropic-to-polar water cycle, increasing polar glaciers and ice caps. The reverse is happening. The Arctic is warming more rapidly than any other part of the planet. Maybe someone needs to write a Hamaker article.

I take my shoes off if those are the rules when I visit some people. If I don't like what's been served for the meal I simply shift the unpalatable to the side of the plate - I don't tell the cook he's incompetent. I don't tell the other guests their enjoyment is all wrong. I use the bathroom in the hall, I don't wander through the host's bedroom to use their ensuite unless I'm invited to do so.

The fact that a site like this is an 'open house' invitation doesn't alter the fact that there are always some rules about acceptable behaviour.

Twice now (here and here) I've offered up advice on how to be a positive contributor here so that we all can benefit from the knowledge you bring to this table. Other than that, I've tried to stay out of the discussion, to see the merits of your position from your point of view, free from being a direct part of the action.

But time and again, you veer off into dissembling, blaming and impugning the integrity of the moderators here. Tell me, do you work at being difficult or does it just come naturally? Because, honestly, I can't tell the difference.

Many of us are intimately aware of dysfunctionality. Either we've grown up with it, lived it or witnessed it close at hand. I'm certainly not perfect and I really try to make allowances for the imperfections of others. But frankly, I resent your implication that by being a commenter and frequenter of this place that I'm a party to this quasi-conspiracy against you.

Tom Loeber - The topics of cloud feedback (including noctilucents) and of sudden regime changes in climate are both interesting, and it would be worthwhile to discuss those. I myself have suggested a thread on cloud feedback; unfortunately, I don't consider myself well enough informed on the topic to contribute that myself. Until we have a thread, though, I'm not going to ramble on regarding that topic on an unrelated thread.

Climate reversals: Perhaps there is some chance of a Younger Dryas type event, although that appears to have been a Northern Hemisphere occurrence, not a global one (perhaps a shutdown of the North Atlantic thermohaline circulation?). But given that we don't know exactly why such events occurred, we don't have any evidence to suspect a climate reversal.

What we do have is significant evidence and known risk factors for amplification of warming - methane release from permafrost and sea-floor clathrate accumulations, for example. Those would have global effects, not regional. Given what we know, those are significant risks down the line, not reversals.

Tom Loeber wrote : "2/3 of Peru under state of emergency for cold not widespread enough for you?"

Once again, you are caught up in the type of argument/belief where you see only part of the answer (the answer you WANT to see) and ignore everything else.
With regard to Peru, you also have to bear in mind that it wasn't simply the cold weather that led to the state of emergency - it was also due to the effects of that cold on a poverty-stricken people who had previously suffered from everything from extreme downpours to extreme drought. The deaths were largely respiratory infections in children, sadly, but such deaths (and, therefore, such a state of emergency) would not have been so widespread in a wealthier country with a more effective health system.
Tragic and extreme but not as doom-laden or prophetic as you seem to think - at least, not unless it becomes a regular occurrence in future.

You obviously need to become more aware of something you yourself stated previously :

Drawing your own conclusions has led you to your 'coming ice-age' belief. Why not step back, look at all the evidence (and in more detail at the stories you are using to 'back-up' your assertions), and see what the reality is as it stands at the moment - cold weather, even very cold weather, is still possible (perhaps more likely in certain areas) in a warming world which isn't heading towards an ice-age.

Oh, and you would look more credible if you were to post less of your conspiracy-theory/censorship thoughts.

I do want to step back and issue a general, heart-felt compliment to you, Tom. Your ideas about noctilucent clouds, tipping points and sudden ice ages is certainly one of the most unique and interesting ideas I've heard in a while.

You should really try to present it in a more formal fashion here, with cited sources, etc. I think you'd find a much better, dialogue-based, discussion of what you bring to this table. I would look forward to reading such a presentation.

Tom,and all record November high temperature here in New Zealand. Your point? "Global" warming means look at temperature of whole globe. If you believe that AGW predicts no more record lows in every region of the world then you are sadly mistaken. Are you going to spam us with all the record high temperatures as well or do you have tunnel vision?

I believe we are experiencing global warming. Who said i didn't? I also believe climate is dynamic and expecting only slow global warming could be a disastrous mistake but, if it doesn't fit what you want to believe, then, by all means, do the junk yard dog dance.

Scaddenp, what was your last winter like? I understand there was some pretty unusual cold and snow.

I see oscillations, winter to summer. I see extremes in both. I see it as a ship rocking on an ocean whose currents are being subjected to new factors, unprecedented factors the consequences of growing powerful thinking life within a finite space. Whether or not thinking life embraces free exchange of information to express intelligence may be a question as to whether or not that listing ship collapses out of what we can endure, Intelligence, fat chance, what with these linear presentations in control of folks with no or little testing of their responsibility and tolerance, seeing the little pieces that challenge status quo are given little space and much denigration, IMHO